Update dependency astro to v4.15.5

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
astro (source)	4.15.4 -> 4.15.5

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Release Notes

withastro/astro (astro)

v4.15.5

Compare Source

Patch Changes

• #​11939 7b09c62 Thanks @​bholmesdev! - Adds support for Zod discriminated unions on Action form inputs. This allows forms with different inputs to be submitted to the same action, using a given input to decide which object should be used for validation.

  This example accepts either a create or update form submission, and uses the type field to determine which object to validate against.

  import { defineAction } from 'astro:actions';
  import { z } from 'astro:schema';
  
  export const server = {
    changeUser: defineAction({
      accept: 'form',
      input: z.discriminatedUnion('type', [
        z.object({
          type: z.literal('create'),
          name: z.string(),
          email: z.string().email(),
        }),
        z.object({
          type: z.literal('update'),
          id: z.number(),
          name: z.string(),
          email: z.string().email(),
        }),
      ]),
      async handler(input) {
        if (input.type === 'create') {
          // input is { type: 'create', name: string, email: string }
        } else {
          // input is { type: 'update', id: number, name: string, email: string }
        }
      },
    }),
  };

  The corresponding create and update forms may look like this:

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